After cutting down the voice chat feature in PlayStation Home, Sony PlayStation Network's Abigail Murphy says that their new 1.05 update brings the feature back but limiting it to users' personal spaces and clubhouses:

PlayStation Home update 1.05 is scheduled to be released on December 22. With this new update, users will be able to use the voice chat within their personal space and clubhouses to communicate and share with friends online.

By clicking on their PlayStation Home icon on the PlayStation Network column of XMB, users will be able to update PlayStation Home to 1.05. Users who are online with PlayStation Home will need to log-off and click on PlayStation Home icon.